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The surprising auroras of Jupiter

An article published in the journal “Nature” describes a research on the auroras on the planet Jupiter and on the differences with those on Earth. A team of researchers led by Barry Mauk of the Johns Hopkins University Applied Physics Laboratory investigated data collected in particular by two instruments aboard NASA’s Juno space probe finding traces of remarkable electrical potentials. They’re aligned with Jupiter’s magnetic field, which accelerates the electrons towards the atmosphere at energies even tenths times higher than those of the Earth’s auroras.

Researchers already knew that Jupiter has the most powerful auroras of the solar system so it was not surprising to see that the electric potential plays a role in their generation. However, despite that potential’s level, it’s observed only sometimes and isn’t the cause of the most intense auroras, as it does on Earth. On Jupiter, the most intense auroras are caused by some turbulent acceleration process that’s still not understood very well.

The latest data from the Juno space probe suggest that when the energy density of the aurora generation becomes more and more powerful, the process becomes unstable and a new acceleration process takes its place. However, Barry Mauk admitted that he and his colleagues must keep on examining the data. His team reviewed in particular the data collected by the the Ultraviolet Spectrograph (UVS) and the Jovian Energetic Particle Detector Instrument (JEDI) instruments.

The highest energies that Barry Mauk and his colleagues are observing in the aurora regions are formidable. The energetic particles that generate the auroras also help to understand the radiation belts of Jupiter, the equivalent of the Earth’s van Allen belts. For this reason, the study of the Earth’s magnetosphere with space probes such as the van Allen probes or the Magnetospheric Multiscale mission (MMS) is also useful in research on other planets.

In the specific case, there’s a comparison between the processes in place on Jupiter and on the Earth and that’s very helpful to improve the models of planetary physics. Research such as this one provides new information on the electromagnetic interaction of different planets with their respective space environments.

These are complex researches that require nearby detections with specific instruments because the ones carried out by the Hubble Space Telescope and the previous space probes that studied Jupiter closely didn’t provide data in the same amount and quality as are possible with Juno.

This research confirms the excellent results the Juno space probe, which entered Jupiter’s orbit on July 4, 2016, is obtaining. A lot of new information were detected on Jupiter’s auroras with these surprises that are already making many scientists busy and expanding our knowledge.